James Ashby, the political aide who accused Speaker Peter Slipper of sexual harassment, is now facing a police investigation into allegations he had sexual relationships with two 15-year-old boys.

The latest explosive twist in the saga was revealed by the ABC's 7.30 program.

The claims come from a Queensland man who contacted Mr Slipper after Mr Ashby launched his case.

The young man says he had a sexual relationship with Mr Ashby in Townsville in 2003, when he was 15 and Mr Ashby was in his mid-twenties.

Mr Ashby moved there from Newcastle, where he had resigned from his job as a radio DJ in controversial circumstances - convicted and fined for making threatening and abusing phone calls to a rival radio host.

The young man's email to Mr Slipper has been obtained by 7.30, and in it he also claims Mr Ashby ended their relationship to enter a relationship with another 15-year-old.

"In 2003 I met James Ashby through a mutual friend. He was working for a radio station and in the process of moving to Townsville," the email said.

"We began a sexual relationship which lasted for a few weeks before James broke it off as he had started a relationship with another person, which lasted two or three years.

"I was 15 at the time, however what we did, under Queensland law, cannot be consented to under the age of 18.

"The guy James broke it off for was also 15 at the time they began their relationship.

"James left me feeling used and disgusted with myself."

7.30 has also seen Facebook messages that Mr Ashby sent to the young man confirming their relationship.

"I really never gave an explanation behind me f***ing off and not saying why," Mr Ashby wrote.

"Strangely enough the reason was so pathetic but I thought I'd share it with you.

"Your mum freaked me out when she walked in on you and me in bed. That did my head in for some strange reason."

Mr Ashby continued the correspondence as he prepared to take on his new job.

"I start my new role as advisor to Australia's speaker of the House this Friday. Shitting myself, absolutely," he wrote.

"I have no idea why your acceptance of this half-arse explanation is needed, but maybe it'll give me some closure for something that's been a long-running issue for me."

'I cannot ignore these allegations'

After the young man sent Mr Slipper this material, the Speaker urged him to take the matter to police.

A few weeks later, Mr Slipper took action himself, writing to Queensland Police Commissioner Bob Atkinson on June 26, and forwarding on the emails and Facebook messages.

"Although the allegations that have come to light predate Mr Ashby's employment with my office, they raise issues of possible criminal conduct. In these circumstances, I cannot ignore the allegations," he wrote in his letter to Mr Atkinson.

Some may well question Mr Slipper's motivations, but the allegations are being taken seriously.

Under the Queensland Criminal Code, sex with minors is an offence punishable by up to 14 years in jail, and 7.30 has confirmed the police are investigating the claim Mr Ashby had sex with underage boys, though it is not yet clear at all whether he will have a case to answer.

"The Queensland Police Service is in the process of determining whether any person authorised to do so wishes to make a complaint and if that is the case, whether there is the evidence to support any prosecution," Queensland police said in a statement to 7.30.

"We will advise in due course the outcome of that investigation."

The ABC has spoken to the young man who made the allegations, but he did not want to be interviewed or to comment.

A spokesman for Mr Slipper says he will not be commenting on the matter.

Opposition Leader Tony Abbott will not comment on the allegations, saying it is a matter for police.

Acting Prime Minister Wayne Swan agrees.

"The allegations last night on the 7.30 were extremely serious. They should be investigated by the responsible authorities," he said.

Shadow Attorney General George Brandis says the allegations have no bearing on Mr Ashby's case against Mr Slipper.